Sealing epoxy resin composition, hardened product, and semiconductor device

Abstract

A sealing epoxy resin composition contains a phosphonium salt shown in Formula (1), an epoxy resin, a hardening agent, and an inorganic filler. In Formula (1), R 1 -R 3 each represent an aryl group having 6 to 12 carbon atoms, R 4 represents an alkyl group having 1 to 4 carbon atoms, R 6 and R 8 each represent either a carboxyl group or a hydroxyl group, R 5 and R 7 each represent either hydrogen or an alkyl group having 1 to 4 carbon atoms, R 9 and R 11 represent hydrogen, R 10 represents either a carboxyl group or a hydroxyl group, and the relation of r≦1 is satisfied.

What is claimed is: 
     
       1. A sealing epoxy resin composition comprising:
 a phosphonium salt shown in Formula (1); 
 an epoxy resin; 
 a hardening agent; and 
 an inorganic filler, 
 
       
         
           
           
               
               
           
         
         where 
         R 1 -R 3  are independent and each represent an aryl group having 6 to 12 carbon atoms; 
         R 4  represents an alkyl group having 1 to 4 carbon atoms; 
         R 6  and R 8  are independent and each represent either a carboxyl group or a hydroxyl group; 
         R 5  and R 7  are independent and each represent either hydrogen or an alkyl group having 1 to 4 carbon atoms; 
         R 9  and R 11  represent hydrogen; 
         R 10  represents either a carboxyl group or a hydroxyl group; and 
         a relation of 0≦r≦1 is satisfied. 
       
     
     
       2. The sealing epoxy resin composition according to  claim 1 , wherein in Formula (1), at least one of R 6  and R 8  represents a carboxyl group. 
     
     
       3. The sealing epoxy resin composition according to  claim 2 , wherein in Formula (1), R 10  represents a hydroxyl group. 
     
     
       4. The sealing epoxy resin composition according to  claim 1 , wherein the phosphonium salt is synthesized by a process including a salt exchange reaction between an alkyl carbonate of quaternary phosphonium and an organic carboxylic acid. 
     
     
       5. The sealing epoxy resin composition according to  claim 1 , wherein a content of halogen ion in the phosphonium salt is 5 ppm or less. 
     
     
       6. The sealing epoxy resin composition according to  claim 1 , wherein the hardening agent contains at least one selected from the group consisting of phenolic compounds and functional compounds generating phenolic hydroxyl groups. 
     
     
       7. A hardened product obtained by hardening the sealing epoxy resin composition according to  claim 1 . 
     
     
       8. A semiconductor device comprising:
 a semiconductor element; and 
 a sealant sealing the semiconductor element, the sealant being composed of the hardened product according to  claim 7 .